ARECACEAE

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            1. SYSTEMATIC POSITION:
            Bentham & Hooker
            Division: Phanerogames (Seed Plants)
                 Class: Monocotyledones
                       Series: Calycineae
                             Family: Arecaceae
           
            2. MORPHOLOGICAL CHARACTERS:
            Habit – A tall, woody unbranched stem bearing a crown of leaves. Some palms are climbing.
            Leaves – Large with well developed petiole, pinnately (feather palm) or palmately (fan palm) divided.
            Inflorescence – Simple or compound spadix, compound spike or profusely branched panicle, enclosed by one or more spathes.
            Flower – Unisexual, mostly monoecious, actinomorphic, hypogynous, sessile, bracteate.
            Perianth – Tepals 6, arranged in two whorls, leathery and fleshy, persistent.
            Androecium – Stamens 6, in 2 whorls, filament free or connate, anthers dithecous, versatile.
            Gynoecium – Tricarpellary, apocarpous or syncarpous, superior, trilocular, ovules 1-2 in each loculus, style short.
            Fruit – Berry or drupe.
              4. COMPARATIVE SYSTEMATIC POSITION AND AFFINITIES:
            Bentham & Hooker have placed the family Arecaceae under the series Calycinae. Engler & Prantl have placed this family under the order Principes, Hutchinson in the order Palmales while Takhtajan, Cronquist and Thorne in the order Arecales.
            Arecaceae is closely related to Araceae. According to Hutchinson, Arecaceae is allied to Pendanaceae on one hand and Agavaceae on the other. He believed that Arecaceae probably originated from Agavaceae. Takhtajan and Cronquist opined that because of the presence of unisexual inconspicuous flowers developing in spadix in both Arecaceae and Araceae, the two families are closely allied.
            The Arecaceae is also considered to be closely related to Liliaceae. The habit of palms resembles those of Dracaena, Yucca, etc. The structure of the pollen grains in the palms and Dracaena are essentially similar. The characters of Arecaceae like perianth segments and stamens in two series as well as a tricarpellary superior ovary recall the similarities with those of Liliaceae.
             5. ECONOMIC IMPORTANCE:
            1. The climbing species of Calamus are also known as canes which is used for making sticks, chairs, baskets, mats, boxes, etc.
            2. The fruit of Cocos nucifera is well known to all – the endosperm and cotyledon of seeds are eaten raw. The dried endosperm yields oil of commerce. The water, which is also a part of endosperm, is used as shooting drink. The fibrous mesocarp of fruit is used in making ropes, bristles of brushes, mats, carpets, etc.
            3. The seeds of Areca catechu also known as betel nuts which are chewed along with the betel leaves.
            4. The sugery juice, also known as toddy, is obtained from young shoot-tips of Borassus flabellifer and Phoenix sylvestris is used for making sugar (gur) and local alcoholic drink (tari).
            5. Many species Palmae are cultivated as ornamental garden plants such as Roystonea regia (royal palm), Ptychosperma macartheri, Levistana chinensis (Chinese fan palm), Chamaerops humilis (European fan palm), etc.

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